Modelling the evolution of oxidative browning during storage of white wines: effects of packaging and closures

Shelf life of products is a key parameter for any company at local and international level that wish to improve their competitiveness; thus, there is a need to search for methods that allow one to predict the shelf life of bottled wines. In this view, the progress of chemical oxidative reactions of six Italian white wines during storage (10\ua0months after bottling), in different packaging, was monitored by means of selected oenological parameters. The optical density at 420\ua0nm, an index of browning, showed a progressive increase that fitted the zero-order kinetic rate. The onset of wine browning was further tested by means of accelerated ageing in controlled temperature conditions which results, modelled using the rate constants approach, showed an Arrhenius-like dependence from temperature, allowing to estimate apparent activation energies of oxidative chemical browning (range: 46.8\u201388.3\ua0kJ\ua0mol 121). Kinetic and thermodynamic approach provided a useful tool to predict quality changes of white wines during storage with respect to packaging conditions